TU-E-BRB-01: Similar-Case-Based Optimization of Beam Arrangements in Stereotactic Body Radiation Therapy.

abstract：PURPOSE:Breast density is a significant breast cancer risk factor. Although various methods are used to estimate breast density, there is no standard measurement for this important factor. The authors are developing a breast density standardization method for use in full field digital mammography (FFDM). The approach c...

journal_title：Medical physics

authors： Heine JJ,Cao K,Beam C

更新日期：2009-12-01 00:00:00

abstract：PURPOSE:Talbot-Lau x-ray interferometry provides information about the scattering and refractive properties of an object - in addition to the object's attenuation features. Until recently, this method was ineligible for imaging human-sized objects as it is challenging to adapt Talbot-Lau interferometers (TLIs) to the r...

journal_title：Medical physics

authors： Hauke C,Bartl P,Leghissa M,Ritschl L,Sutter SM,Weber T,Zeidler J,Freudenberger J,Mertelmeier T,Radicke M,Michel T,Anton G,Meinel FG,Baehr A,Auweter S,Bondesson D,Gaass T,Dinkel J,Reiser M,Hellbach K

更新日期：2018-06-01 00:00:00

abstract：:Setting up and maintaining video display monitors properly will help to reduce display variation and improve overall presentation of the radiological image. Display monitor gray-scale characteristics were examined using the SMPTE test pattern. This test pattern may be used as a standard for adjusting brightness and co...

journal_title：Medical physics

authors： Nawfel RD,Chan KH,Wagenaar DJ,Judy PF

更新日期：1992-05-01 00:00:00

abstract：:A method is described for obtaining S values between a tumor and its host organ for use with the MIRD formalism. It applies the point-source specific absorbed fractions for an infinite water medium, tabulated by Berger, to a rectangular solid of arbitrary dimensions which contains a rectangular tumor of arbitrary dime...

journal_title：Medical physics

authors： Stinchcomb TG,Durham JS,Fisher DR

更新日期：1991-05-01 00:00:00

abstract：PURPOSE:The objective of this study is to evaluate requirements for radionuclide-based solid tumor therapy by assessing the radial dose distribution of beta-particle-emitting and alpha-particle-emitting molecules localized either solely within endothelial cells of tumor vasculature or diffusing from the vasculature thr...

journal_title：Medical physics

authors： Zhu X,Palmer MR,Makrigiorgos GM,Kassis AI

更新日期：2010-06-01 00:00:00

abstract：PURPOSE:The Imaging and Radiation Oncology Core Houston (IROC-H) (formerly the Radiological Physics Center) has reported varying levels of agreement in their anthropomorphic phantom audits. There is reason to believe one source of error in this observed disagreement is the accuracy of the dose calculation algorithms an...

journal_title：Medical physics

authors： Faught AM,Davidson SE,Fontenot J,Kry SF,Etzel C,Ibbott GS,Followill DS

更新日期：2017-09-01 00:00:00

abstract：:In this study, BrachyDose, a recently developed EGSnrc Monte Carlo code for rapid brachytherapy dose calculations, has been benchmarked by reproducing previously published dosimetry parameters for three brachytherapy seeds with varied internal structure and encapsulation. Calculations are performed for two 125I seeds ...

journal_title：Medical physics

authors： Taylor RE,Yegin G,Rogers DW

更新日期：2007-02-01 00:00:00

abstract：:Motion and deformation of the cardiac wall may be measured by following the positions of implanted radiopaque markers in three dimensions, using two x-ray cameras simultaneously. Regularly, calibration of the position measurement system is obtained by registration of the images of a calibration object, containing 10-2...

journal_title：Medical physics

authors： Muijtjens AM,Roos JM,Arts T,Hasman A

更新日期：1999-02-01 00:00:00

abstract：PURPOSE:The x-ray performance evaluation of digital x-ray detectors is based on the calculation of the modulation transfer function (MTF), the noise power spectrum (NPS), and the resultant detective quantum efficiency (DQE). The flat images used for the extraction of the NPS should not contain any fixed pattern noise (...

journal_title：Medical physics

authors： Konstantinidis AC,Olivo A,Speller RD

更新日期：2011-12-01 00:00:00

abstract：PURPOSE:Many biological objects, including neuronal dendrites, blood vasculature, airways, phylogenetic trees, produce tree structured data. Current methods of analysis either ignore the complex structure of trees or use distance-based methods which limit the scope of multivariate modeling. METHODS:We propose a branch...

journal_title：Medical physics

authors： Roy Choudhury K,Skwerer S

更新日期：2018-03-01 00:00:00

abstract：:Inherent in the line-spread function approach in modulation transfer function (MTF) determinations is the use of a microdensitometer to scan the density pattern resulting from the line exposure. In such a procedure, loss of fidelity in the distribution being scanned is expected. This loss is due in part to the use of ...

journal_title：Medical physics

authors： Villafana T

更新日期：1975-09-01 00:00:00

abstract：PURPOSE:Small animal immobilization devices facilitate positioning of animals for reproducible imaging and accurate focal radiation therapy. In this study, the authors demonstrate the use of three-dimensional (3D) printing technology to fabricate a custom-designed mouse head restraint. The authors evaluate the accuracy...

journal_title：Medical physics

authors： Zarghami N,Jensen MD,Talluri S,Foster PJ,Chambers AF,Dick FA,Wong E

更新日期：2015-11-01 00:00:00

abstract：:The modulation transfer function (MTF) of a screen-film system can be measured by two methods, i.e., a slit method with Fourier transform on the line spread function and a square-wave response function (SWRF) method. However, it is still uncertain whether MTFs obtained by the two methods are identical. In this study, ...

journal_title：Medical physics

authors： Morishita J,Doi K,Bollen R,Bunch PC,Hoeschen D,Sirand-rey G,Sukenobu Y

更新日期：1995-02-01 00:00:00

abstract：BACKGROUND:Deep learning methods for radiomics/computer-aided diagnosis (CADx) are often prohibited by small datasets, long computation time, and the need for extensive image preprocessing. AIMS:We aim to develop a breast CADx methodology that addresses the aforementioned issues by exploiting the efficiency of pre-tra...

journal_title：Medical physics

authors： Antropova N,Huynh BQ,Giger ML

更新日期：2017-10-01 00:00:00

abstract：:Absorbed doses from main charged-particle beams and charged-particle fragments have been measured with high accuracy for particle therapy, but there are few reports for doses from neutron components produced as fragments. This study describes the measurements on neutron doses produced by carbon beams; microdosimetric ...

journal_title：Medical physics

authors： Endo S,Tanaka K,Takada M,Onizuka Y,Miyahara N,Sato T,Ishikawa M,Maeda N,Hayabuchi N,Shizuma K,Hoshi M

更新日期：2007-09-01 00:00:00

abstract：PURPOSE:The absolute dose rate of the Imaging and Medical Beamline (IMBL) on the Australian Synchrotron was measured with a graphite calorimeter. The calorimetry results were compared to measurements from the existing free-air chamber, to provide a robust determination of the absolute dose in the synchrotron beam and p...

journal_title：Medical physics

authors： Harty PD,Lye JE,Ramanathan G,Butler DJ,Hall CJ,Stevenson AW,Johnston PN

更新日期：2014-05-01 00:00:00

abstract：:The dynamic range of the gray level of a digital image is limited by the noise it contains. Two statistical methods called "runs test" and "join-count statistic" are used to measure the noise level in a digital image. A residual image is formed by subtracting an original image from its smoothed version. Theoretically,...

journal_title：Medical physics

authors： Chuang KS,Huang HK

更新日期：1993-01-01 00:00:00

abstract：PURPOSE:In using flat panel detectors (FPD) for cone beam computed tomography (CBCT), pixel gain variations may lead to structured nonuniformities in projections and ring artifacts in CBCT images. Such gain variations can be caused by change in detector entrance exposure levels or beam hardening, and they are not accou...

journal_title：Medical physics

authors： Altunbas C,Lai CJ,Zhong Y,Shaw CC

更新日期：2014-09-01 00:00:00

abstract：PURPOSE:Consistency verification between the data from treatment planning system (TPS), record and verification system (R&V), and delivered recorder with visual inspection is time consuming and subject to human error. The purpose of this work is to develop a software tool to automatically perform such verifications. M...

journal_title：Medical physics

authors： Chen G,Li X

更新日期：2012-06-01 00:00:00

abstract：PURPOSE:One technical barrier to patient-specific computed tomography (CT) dosimetry has been the lack of computational tools for the automatic patient-specific multi-organ segmentation of CT images and rapid organ dose quantification. When previous CT images are available for the same body region of the patient, the a...

journal_title：Medical physics

authors： Peng Z,Fang X,Yan P,Shan H,Liu T,Pei X,Wang G,Liu B,Kalra MK,Xu XG

更新日期：2020-06-01 00:00:00

abstract：PURPOSE:IAEA TRS-398 notes that cylindrical ionization chambers are preferred for reference proton dosimetry. If a cylindrical ionization chamber is used in a phantom to measure the dose as a function of depth, the effective point of measurement (EPOM) must be taken into account. IAEA TRS-398 recommends a displacement ...

journal_title：Medical physics

authors： Sugama Y,Nishio T,Onishi H

更新日期：2015-07-01 00:00:00

abstract：PURPOSE:Intracavitary accelerated partial breast irradiation (APBI) has become a popular treatment for early stage breast cancer in recent years due to its shortened course of treatment and simplified treatment planning compared to traditional external beam breast conservation therapy. However, the exit dose to the ski...

journal_title：Medical physics

authors： Raffi JA,Davis SD,Hammer CG,Micka JA,Kunugi KA,Musgrove JE,Winston JW Jr,Ricci-Ott TJ,DeWerd LA

更新日期：2010-06-01 00:00:00

abstract：:In many of brachytherapy procedures, a large amount of radioactive sources are used to deliver desired doses to the target volume. It is both the federal regulation recommendation (U.S. Nuclear Regulatory Commission, 10 CFR 35.432) and recommendations of the American Association of Physicists in Medicine (AAPM) [Kutch...

journal_title：Medical physics

authors： Yue NJ,Haffty BG,Yue J

更新日期：2007-06-01 00:00:00

abstract：:Because of the high energy of the treatment beam, contrast of portal verification films is very poor. A simple contrast enhancement technique is described which we have labeled selective histogram equalization (SHE), to improve visualization of double-exposure portal images and this facilitate the beam verification pr...

journal_title：Medical physics

authors： Crooks I,Fallone BG

更新日期：1993-01-01 00:00:00

abstract：:A technique was developed to reduce the size and magnitude of the hot and cold spots in the abutting regions of photon and electron fields. The photon and electron fields were set up such that the photon field extended approximately 2 cm into the electron field in the abutting region. The region of the photon beam tha...

journal_title：Medical physics

authors： Li JG,Xing L,Boyer AL,Hamilton RJ,Spelbring DR,Turian JV

更新日期：1999-11-01 00:00:00

abstract：PURPOSE:To obtain on-treatment volumetric patient anatomy during respiratory gated volumetric modulated arc therapy (VMAT). METHODS:On-board imaging device integrated with Linacs offers a viable tool for obtaining patient anatomy during radiation treatment delivery. In this study, the authors acquired beam-level kV im...

journal_title：Medical physics

authors： Choi K,Xing L,Koong A,Li R

更新日期：2013-04-01 00:00:00

abstract：:One of the key components in modern LINAC room shielding design is the amount of 90 degrees head leakage radiation levels. With the general clinical acceptance of intensity-modulated radiation therapy (IMRT) technique, accurate knowledge of this quantity has become even more important. Measurement of 90 degrees head l...

journal_title：Medical physics

authors： Li Z,Mutic S,Low D

更新日期：2006-09-01 00:00:00

abstract：:This study presents experimental results about the effective depth of penetration and about the radiofrequency (rf) power absorption in humans as a function of frequency. The frequency range investigated covers 10 up to 220 MHz. For the main part, the results were derived from bench measurements of the quality factor ...

journal_title：Medical physics

authors： Röschmann P

更新日期：1987-11-01 00:00:00

abstract：:This paper examines the distributions of the SAR (specific absorption rate) ratio and temperature elevation when an ultrasound beam propagates through the interface of muscle and bone. This interface is regarded as a flat boundary to partition the energy of the ultrasound beam, and the analytical solution of temperatu...

journal_title：Medical physics

authors： Lin WL,Liauh CT,Chen YY,Liu HC,Shieh MJ

更新日期：2000-05-01 00:00:00

abstract：PURPOSE:Episcleral eye plaque brachytherapy has been utilized in the treatment of intra-ocular malignancies, delivering large prescription doses to the apex of the tumor. Advances in dose calculation and image guidance, via calibrated fundus images, enable localization of the tumor and determination of dose to the macu...

journal_title：Medical physics

authors： Guida K,Niermann K,Malcolm A,Sternberg P,Munn G,Coffey C

更新日期：2012-06-01 00:00:00